Wind power has been harnessed and utilized for centuries to allow for transportation (sailboats, for instance), for food generation (windmills), and, much more recently, as a source of electricity generation (wind turbines). Such a natural resource accords potential unlimited supplies of power generation, of course, without the other drawbacks of the current primary electrical generation methods.
The generation of electricity is of enormous importance in terms of bringing modern luxuries to a large amount of the world's population. However energy generation has proven to be both complex and rather difficult to accomplish from an efficiency and environmental standpoint. Electricity is typically created through the conversion of power sources to electron generation. The general and predominant methods followed for such a purpose include fossil fuel burning (converting heat to electricity), nuclear power (converting fusion of radioactive materials), capturing and storing solar power, hydroelectricity (harnessing water movement to drive turbines), and, of course, wind power (utilizing wind to drive an electricity-producing turbine).
Fossil fuels are currently utilized within most electrical power generating systems in the world due to the large supply of coal and other such fuels that can easily burn to generate the needed heat for such a purpose. Unfortunately, this method is well-known to cause the emission of undesirable gases into the atmosphere (carbon dioxide, sulfur dioxide, for instance). As well, however, coal also may include certain heavy metals (mercury, chromium, and the like) that, upon incineration of the coal itself, may be released into the atmosphere as well unless removal means are implemented for such a purpose. Basically, though, this electricity generating method is problematic, particularly in the future with the expected growth in worldwide populations demanding greater amounts of power, thereby theoretically, at least, increasing the expected amount of burning fuels and subsequently polluting emissions as a result.
Nuclear power is considered a potentially “cleaner” alternative to fossil fuels because nuclear power generation does not generate the undesirable gas emissions that coal fired and other fossil fuels plants produce; however, the necessity for radioactive materials, both in supply and eventual destruction or long-term storage, has created considerable resistance to such programs.
Solar power has proven rather difficult to implement, particularly on a large-scale level. The complexities involved with capturing and storing such power allows for small-scale, individual, methods of this sort, but large-scale implementation has proven elusive. Furthermore, the storage necessity is of utmost importance considering the lack of constant reliability of a solar power source. To provide a sufficient amount of power through constant variations in solar exposure is rather difficult, in other words.
Hydroelectricity has been possible upon the creation of dams over certain moving water sources. The directional flow of fluids through a turbine creates the necessary rotational movement thereof to generate electricity as a result. Although such a large-scale procedure has been workable in many areas of the globe, the ability to locate and implement such a system without simultaneously impacting the surrounding environment (though, for example, the redirection of water sources) has, in many cases, been a problem. Flooding, although alleviated in some situations through dam erection, at times is exacerbated through such a method. Likewise, dam building has also proven to reduce the available water to some areas, thus providing an unwanted tradeoff of water for electrical power. In general, hydroelectricity is reliant primarily on finding a suitable riparian source and handling the overall situation properly; the numbers of effective electrical generating sources provided in this manner has been minimal at best, as a result. The difficulty in locating and suitably utilizing sufficient sources of moving water in the future for such a purpose also militates against long-term plans of hydroelectric solutions for power generation.
Wind power, on the other hand, can theoretically be available anywhere on the planet. Through differing pressures within the atmosphere, wind can be generated at any speed and, much like hydroelectricity, may be channeled through a turbine to provide the necessary rotational energy to create electrical charges. The main problems affecting such a system lie in the locating and sustaining at least minimal wind speeds to generate minimal electrical charges, as well as the possibility of very high winds above a certain threshold that could damage the machinery involved. Particularly with large bladed devices, if wind speeds exceed a certain level, shutdown is generally required to protect the expensive machines. Large blades are generally utilized in order to generate the greatest amount of turbine activity in relation to the typical wind speeds available in a certain area. In other words, since wind speeds are very hard to predict, large blade devices are utilized quite often in order to compensate for potentially low levels to generate the greatest amount of fluid stream through the subject turbine. As noted above, however, this structural configuration may actually become highly problematic as very high wind speeds may damage the turbine through excessive rotational movement not to mention the possibility of large blade damage through high wind shear exposure. Additionally, due to the utilization of large blades, these devices are often very large. Wind turbines can be installed in a group which is sometimes referred to as a wind farm. Thus, the installation takes up a considerable amount of space.
As alluded to above, wind turbines have been utilized for various uses in the past, although their importance for electricity generation has only recently been of note. Wind turbines usually contain a propeller-like device, termed the “rotor”, which is faced into a moving air stream. As the air hits the rotor, the air produces a force on the rotor in such a manner as to cause the rotor to rotate about its center. The rotor is connected to either an electricity generator or mechanical device through linkages such as gears, belts, chains or other means. Such turbines are used for generating electricity and powering batteries. They are also used to drive rotating pumps and/or moving machine parts. It is very common to find wind turbines in large electricity generating “wind farms” containing multiple such turbines in a geometric pattern designed to allow maximum power extraction with minimal impact of each such turbine on one another and/or the surrounding environment.
Although such devices provide effective means for this purpose, drawbacks have created limited usage in the past. For example, the reliability of such devices to provide effective electricity generation in variable wind speed environments has been problematic. Although some locations around the globe are known to harbor high wind speed environments on a reliable basis (mainly over bodies of water), the ability to utilize less open expanses for wind farms for this purpose has proven difficult to increase wind turbine usage worldwide. In other words, the lack of localities with reliable, sustainable wind levels, coupled with the difficulties in storage and transfer of electricity from such locations that do exhibit such favorable characteristics, has been a difficult threshold issue to overcome in expanding wind power generation. More urban locations are generally frowned upon due to the presence of obstacles to open wind areas (for instance, buildings, trees, and other obstructions) and thus do not typically allow for suitable laminar air flow possibilities for wind farms to be worthwhile under current technological levels. An ability to provide effective low wind areas with reliable wind power generating devices has heretofore been difficult to accomplish, as noted above.
The basic problem with low wind areas lies in the necessity of creating suitable and appreciable rotational movement of the subject turbine at a rate that generates the needed minimal electrical charge on a continuous basis. Turbines of this sort include a plurality of blades that create the necessary rotational energy upon exposure to an air stream passing therethrough. As such, proper rotational movement of the turbine relies specifically upon the wind speed present within the throat of the air intake; the higher the speed, the greater the possible rotation of the turbine, and, consequently, the greater the level of electrical generation. Low wind areas thus create distinct problems for wind turbines as the need to increase throat speed relies primarily on the environmental conditions for overall effectiveness.
Some developments have been made in order to attempt to provide artificial increases in throat speed in the past. Notably, however, every past attempt relied upon modifications of the turbine exhaust system. One significant development proposed generating a vortex that creates a vacuum to possibly create increased air pressures and thus greater air movement through the turbine itself. Unfortunately, a number of drawbacks exist with such a system. For instance, by relying upon the exhaust system to initiate the vacuum generation, such a system requires an initial wind speed generation to effectuate the actual vacuum subsequent to air intake utilization. In other words, in order for this system to function, it appears that low wind systems would still create a lack of sufficient air stream speed to create the necessary vacuum in the first place. Secondly, such a system does not take into account the potential for efficiency reductions due to even distributions of air streams on the turbine blade surfaces. With an even level of air stream introduction onto all turbine surfaces, and through the presence and utilization of an evenly generated and applied vacuum thereafter, the turbine itself may not perform to the level it was designed. Lastly, there is no compensation within this prior device to permit reductions in air speed through the subject turbine should the wind speed as introduced grow too high. With the static design, in the exhaust the vacuum generation would continue indefinitely, apparently, without concern as to the degree of strain on the turbine should the air stream velocity increase to a maximum level.
Thus, there exists a need to harness the very clean wind power natural resource to a degree that low wind speeds may still generate effective electrical generation while simultaneously permitting a manner of controlling the velocity of air streams through the subject turbine during high wind events in order to reduce the propensity of turbine damage in such situations. To date, reliable technologies to overcome such drawbacks have been unavailable to the industry.